<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Insert title here</title>
</head>
<body>
	<!--  
		如果一个表单有上传，那么必须method="post",enctype="multipart/form-data"
	 -->
	<form action="upload" 
		  method="post"
		  enctype="multipart/form-data">
		  
		  用户名: <input type="text" name="username"/>   <br>
		  头像：  <input type="file" name="uploadfile" accept=".png,.gif,.jpeg"/> <br>
		  <input type="submit" value="提交"/>
	</form>
</body>
</html>